Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.apo.nmsu.edu/arc35m/Instruments/ARCTIC/Development/ImagerPDR/grizli_performance.pdf Дата изменения: Thu Dec 5 20:44:30 2013 Дата индексирования: Thu Feb 27 21:08:29 2014 Кодировка: Поисковые слова: hawaii

GRIZLI Science Performance Goals Includes also some performance goals for telescope and software 16 October 2011 A. Instrument specs 1. Delivered image quality, in each filter, across entire FOV Goal: 0.5" FWHM, with well-behaved PSF, at high altitude (low airmass) 2. Limiting magnitude Goal: 26th mag in griz gives S/N=10 in 3 min exposure sky-limited in all filters with no moon 3. Exposure time - minimum exposure <= 1 sec, with shutter illumination pattern repeatable (able to calibrate to 0.1%) - maximum exposure at least 10 minutes, more for narrowband option 4. Readout Goal: 10 seconds for all 4 chips in parallel 5. Detector performance Goals: - read noise < 5 e- per (binned 2x2) pixel - dark current < 1 e- per (binned 2x2) pixel in 5 minutes - full well should be close to or slightly above saturation limit - linear response to at least 40K DN (assuming 63K range/saturation) 6. Throughput Goal: 75% throughput 7. Fringing Goals: (for 3 min exposure) - less than 1% in i - less than 5% in z 8. Scattered light Goal: less than 0.1% effect over full field 9. Optical system performance - optical system performance in each of griz measured and provided to high accuracy. - Should be constant across FOV and stable in time. - Provide comparison to standard SDSS passbands, e.g. http://www.sdss.org/dr3/instruments/imager/#filters - Feasibility of transformation to standard SDSS system demonstrated.


10. Alignment of images Goal: sky coverage of different filters overlaps at 99% level 11. Metrology from instrument reported to Hub/TUI, placed in image headers as appropriate B. Next items also depend on telescope 12. Field of view Goal: 10' diameter circular unobstructed FOV 18' diameter FOV with modest vignetting by tertiary baffle 13. Guiding Goal: centroid shift less than 0.2" for three minute exposure 14. Focus Goal: Fast focusing method, and ability to update focus quickly while observing. C. Next items relate to flatfielding, image processing, software, future upgrades 15. Photometry Goal: Ability to take out of focus images of bright objects, and flatfield to obtain competitive differential photometry, 0.001 mags precision Goal: Ability to do competitive absolute photometry to obtain 0.01 mag precision (depends on flatfielding, scattered light, fringing) 16. Software to process and co-add images quickly (needed if using short exposures for on-chip guiding) 17. Photometric transformation from instrument griz to SDSS griz 18. Geometric transformations between griz images 19. Narrow band filter specs, TBD.